Hydrostatic feed



Patented Jan. 27, 1948 UNI-'E ED STATES OFFICE HXDROSTATlG n Frederick A. Wagner, Oakland, Calif..

@riginal application January 12; 19u74 Serial No.. l 12.(l,2.4:5110w Patent- No. 2,152,233', datedMarch 28 1939.., llividlnV and this application- Eebruary 133.1939;v Serial No. 256,091-

1. This invention relates toyhydrostatic. or hy#- draulic feed apparatus of" the type disclosed in my copending patent application filed under Se-v rial No. 120,245 on January 12, 193'?- (now'ratentI No. 2,152,293), and constitutes a divisional appli@ cation thereoff' drawn tocover the modification of the invention shown in'FigureB of said copending application. Y

The object of the present invention is t0 provide a simple, effective,V hydraulically operated power cylinder or plunger -feed bar-"of more general application than the one claimed in my copending application., Particular features andv advantages ofthe invention will appear in the following description and, accompanying drawings.

In the drawings:

Figure 1 is a longitu dinalzsectionl of the apparatus. Y

Figure 2 isan enlarged detached sectionalView'k of the controlling valve of Figure 1.

Figure 3 is a view similar to that of Figure 2. but with the valve turned to on position.

Figure 4 is a sectional view of Figure 1 taken along the line 4 4 thereoi.,

Briefly described the present invention relates to the special combination of a longitudinally movable plunger or piston work banner feed bar., operating in a cylinder, with a spirally grooved oil pumping rotor operating on the viscosity prin;- ciple only, controlled by a multiple valve so as, to control the flow of oil (or other viscousliquid) under pressure to either end of the work-bar piston, or by-pass the oil from one end of the piston to the other, or shut the oil oli entirely from the piston to lock the work or feed bar in any position. Other advantages of the construction will any number lof pistonv ringsV 35'-tting nicely within the cylinder 34. i

The work bar 3 is preferably round and'is slid- Aably supported inheads 52,A 53 secured in any desired manner to the ends of cylinder 3l!I and preferably fitted with close fitting bearing bush-y ings 54--55 to permit the bar 3 to slide, yet pro-A vide an oil tight joint at each end ofthe cylinder. Optionally any kind of stuing boxes maybe used at these points, though with the viscous oil intended to be used in the apparatus it-will not leak 3 Claims.. (Cl.- 60--520 `trolling valve operates.

' i 42 inthe? valve housing-connected with the low-- ermost of the recesses 49,Y and at opposite sides lill 2 even without. packing if4 made'. nicely! The` work bar is'. here shown with. a tool*` 2 lat its` outer: end to constitute a. boringfbar, though it should vbe noted that 'the movement, of the bar or plunger may be used to carry out any Work for whichy it isi adapted.

Cylinder 34: is rigidly mounted over or on the controlling valve 'housing 45 in which the con- The Yvalve may, take various formsv but is hereishown with a revolvalole valve-[plug 45' smoothly mounted for rotationin the valve housing l5 and'held in position by acap 56; thev valve, plugy being provided Awith a suitable handleV 5T for turning the plug. The plug. is farmed with suitable ports t8, 48' which are laterally offset and extend independently through the plugr lto opposite points in the diameter,A but both opening Vat their, ends, When the plug is. turned;i to any ofive recesses 49 formed in the bore7 oi the valve-housing- Theupper two of. the recesses E9 are respectively connected toopposite endsvof the. cylinder 3,4 asbyY pipes` 43., etand passages. 43', 44', while` two. of thelower recesses communicate respectively bypassages llv and del. toy opposite ends ofL a short cylinder v.iiiornnecl, innthe'valve; housing; beneaththe plug, and vwhich cylinder is also con nected fromendto end by a byepass` passage 58 formed in thebase of `the-valve housing.

Within the-fshortcylinder 58 is a nicely tting cylindricalrotor `Ell formed with a central-peripheral channel 42 inl registerwith apassageway of'v channelfZ vthe rotoris.; formed respectively with a very shallow right. andleft handv spiral groovasoas to forceV oil from opposite ends of the rotor cylinder into; channel l2-,andout of passagellZ asthe rotor is revolved. Y

The rotor-is blocked against endwise movement in' its cylinder, and it mayy be iormed integralA with an operating shaftv 38 or may be secured:

In operation, all of the passages, ports and cylinders are kept completely filled with oil, and at one end of the rotor cylinder is a vertically extending passageway 50 communicating with an upwardly extending pipe 50 which carries at its upper end an elevated oil cup or reservoir 46 and always open at its lower end to the intake ends .of the rotor for insuringthe automatic replenishing of any slight oil leakage from the apparatus in use.

With the valve plug turned to the position shown in Figure 1 the oil completely filling both ends of the power or feed cylinder 34, the oil is free to travel from either end to the other by way of pipes 43, 44 and the plug ports which are freely open through the valve housing passages to opposite ends of rotor cylinder 58 in turn openly connected by passage 59-so that it leaves the feed bar 3 free for sliding back and forth in its cylinder mounting.

' With the valve plug turned to position of Figure 3 the plug ports are not open to pipes 43, 44 but are both closed off from `the pipes so that the oil in the feed bar cylinder is blocked against movement and the feed bar is locked.

With the valve plug turned to position of Figure 2 the plug port 48 is opento pipe 44 and to the center of the rotor through passage 42', while the other plug port 48' is open to pipe 43 and to one end of the rotor cylinder and also to the other end by way of passage 59, so that if the rotor is turning in direction of the arrow oil will be drawn from both ends of the rotor cylinder and forced out of channel42 through passage 42', port 48 and pipe 44 to the right hand end of cylinder 34 and force the feed bar to the left.

A glance at Figure 3 will make it plain that by rocking the plug either to the left or right port 48 may bring either end of the feed or power cylinder 34 into operation connection with the rotor oil outflow channel 42 while relieving the oil from the opposite end of the feed cylinder by way of the by-pass channel 59 as described for Figure 2. Also that by careful turning of the valve plug the ports 48-48' can be opened to any degree so as to control the amount of oil flowing through in both directions to and from the power cylinder, and thus control the speed of the bar.

The nature of the apparatus is such that when the valve plug 45' is turned to position of Figure 3 to close off any passage of oil through the plug, a continued turning of the rotor will do no harm, for when it builds up a pressure equal to its capacity it will simply revolve the oil in its spirals as a unit with the rotor.

The character of the spiral grooves in the rotor are very important for it must be distinctly understood that the rotor is not a screw pump as the term is generally understood, for if the spiral grooves were at all in the nature of a thread of any depth such as 1/8", 1A" or l/" in depth there would be no usefu1eifect produced in the apparatus as no usable working pressure could be built up in the power cylinder, except perhaps at tremendous 4Speeds of rotation which would be prohibitive. Whereas, as explained more fully in my copending application, with a rotor of about 21/2" in diameter and with the spiral grooves very shallow-preferably between aime to 2911000" and the oil used is machine oil of about an S. A. E. viscosity ranging from about 30 to 4G, pressures of from 100 to 400 lbs. will be developed in a 2 or 3 inch power cylinder even with the rotor being turned as slow as one revolution per second, yet

4 if the spiral groove were deep, no useful result could be produced.

The spiral grooves are preferably about an eighth of an inch wide and of double or triple lead and the form may be varied considerably from a true spiral as more fully set out in the copending application (Patent No. 2,152,293) and wherein modifications of the rotor are shown and its size and action and pressures developed, are more completely explained.

It will be evident from the above description that other types of multiple-way valves or a plurality of ordinary valves operatively connected together to produce the result described, may be used in place of the revolvable plug valve shown, as the type shown was selected also to make the drawing more easily understood.

It will also be evident that while I prefer to use a double opposed spiral rotor as it avoids any end pressure, and also maintains the low or suction pressure at both bearings so that a through driving shaft may be used without danger of forcing oil along the shaft to leak beyond the bearings, and thus also avoids the use of any packing boxes on the shaft bearings, yet the rotor may have only the right or left hand spiral portion, as either half of the rotor could be left blank, but the arrangement shown avoids all end thrust.

From the above explanation of the action of the rotor on a viscous oil, it will be evident that the proper grade and viscosity of the oil is important, the other liquids or solutions of similar viscosity to that of the oil set out may also bek used, and are intended to be included in the term oil as used herein. However as thin oils such as kerosene, turpentine. also water, alcohol. gasoline, and other substantially non-viscous liduids will not operate at all in the apparatus nor will greases such as lubricating greases, operate in the apparatus to produce any useful result. .it is apparent that the invention is not a mere substitution of a screw pump for other types nf pumps used heretofore to operate a power cylinder, but as the special rotor operating with a viscous oil at once yields a simplicity of construction free L of the rotor, or locking the power cylinder automatically if the rotor should stop, and nally. of greatest importance for machine tool feed purposes it is the only arrangement known to me which of relatively small size and operated at slow speeds will produce a steady longitudinal motion of the work-bar entirely free from any pump pulsations whatever, and which are inherent in every type of pump ever applied to or which is at all practicable for operating such a feed or work bar, all features never combined before in any such a power cylinder without much more elaborate and costly apparatus. and its valve has been proven out by actual shop tools made and sold by me embodying this feature for some time in successful use, I feel entitled to broad coverage in bringing the elements together in the novel manner set out and covered in my appended claims, and for any purpose or use to which the combination can be applied.

I therefore claim:

1. A machine feed comprising in combination a hydraulic cylinder, a piston reciprocable in said cylinder and having a piston rod slidably extending from the cylinder and constituting a machine feed bar, a pump for supplying liquid under pressure to said cylinder, piping extending to and from the inlet and outlet of the pump to opposite ends of the cylinder, reversing valve means forming a part of and connected in said piping for controlling the flow of liquid to and from said pump and opposite ends of the cylinder for reciprocating the piston and feed bar, said pump comprising a closed housing with a cylindrical rotor rotatably fitting therein and having a shaft extended from the housing for rotating the rotor, said rotor having two groups of helical viscosity pump grooves, respectively right and left hand arranged in endwise relation freely open at their remote and adjacent ends respectively at all points in the revolution of the rotor to liquid inlet and outlet spaces within the pump housing constituting respectively said inlet and outlet of the pump, said spaces being large enough to always maintain the full flow area of the revolving ends of said grooves so that liquid pumped by rotating the rotorvwill flow contin uously without pulsation from the inlet spaces to the outlet space, the helical grooves of the rotor being of a shallow depth adapted to operate on the viscosity principle with a viscous oil as the hydraulic liquid and incapable of building up any useful pressure with water for the purpose set out.

2. A machine feed comprising in combination a hydraulic cylinder, a piston reciprocable in said cylinder and having a piston rod slidably extending from the cylinder and constituting a machine feed bar, a pump for supplying liquid under pressure to said cylinder, piping extending to and from the inlet and outlet of the pump to opposite ends of the cylinder, reversing valve means forming a part of and connected in said piping for controlling the flow of liquid to and from said pump and opposite ends of the cylinder for reciprocating the piston and feed bar, said pump comprising a rotatable cylindrical rotor f1tting within a closed housing and provided with a shaft extending from the housing for operating the rotor, said rotor having two groups of helical viscosity pump grooves, respectively right and left hand arranged in endwise relation freely open at their opposite ends respectively at all points of their revolution to inlet and outlet spaces within the pump housing constituting respectively said inlet and outlet of the pump, said spaces being large enough to always maintain the full fiow area of the revolving ends of said grooves so that liquid pumped by rotating the rotor will flow continuously without pulsation from the inlet end space to the outlet end space, and a port freely open to and connecting the spaces at the remote ends of the rotor, the helical grooves of the rotor being of a shallow depth adapted to operate on the viscosity principle with a viscous oil as the hydraulic liquid and incapable of building up any useful pressure with Water for the purpose set out.

3. A machine feed comprising in combination a hydraulic cylinder, a piston reciprocable in said cylinder and having a piston rod slidably extending from the cylinder and constituting a machine feed bar, a pump for supplying liquid under pressure to said cylinder, piping extending to and from the inlet and outlet of the pump to opposite ends of the cylinder, reversing valve means forming a part of and connected in said piping for controlling the flow of liquid to and from said pump and opposite ends of the cylinder for reciprocating the piston and feed bar, said pump comprising a rotatable cylindrical rotor fitting within a closed housing and provided with a shaft extending from the housing for operating the rotor, said rotor having a plurality of helical viscosity pump grooves freely open at opposite ends respectively to inlet and outlet spaces Within the pump housing constituting respectively said inlet and outlet of the pump, said spaces being large enough to always maintain the full flow area of the revolving ends of said grooves so that liquid pumped by rotating the rotor will flow continuously without pulsation from the inlet space to the outlet space, the helical grooves of the rotor being of a shallow depth adapted to operate on the viscosity principle with a viscous oil as the hydraulic liquid and incapable of building up any useful pressure with water for the purpose set out.

FREDERICK A. WAGNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,126,812 McQueen Feb. 2, 1915 1,134,048 Isberg Mar. 30, 1915 1,139,091 Pratt May 11, 1915 1,343,117 Dana June 8, 1920 1,395,001 McDonald Oct. 25, 1921 1,448,079 Noeggerath Mar. 13, 1923 1,448,080 Noeggerath Mar. 13, 1923 1,454,396 McDonald May 8, 1923 1,582,468 Heald et al Apr. 27, 1926 1,641,300 Spencer Sept. 6, 1927 1,665,931 Noeggerath Apr. 10, 1928 1,672,561 Ernst June 5, 1928 1,690,069 Ferris Oct. 30, 1928 1,760,915 Robson June 3, 1930 1,843,082 Ferris et al. Jan. 26, 1932 1,848,006 Ferris Mar. 1, 1932 1,918,426 Radnor July 18, 1933 1,948,951 Walker Feb. 27, 1934 1,974,657 Rodier Sept. 25, 1934 FOREIGN PATENTS Number Country Date 173,048 Great Britain Dec. 16, 1921 174,984 Great Britain Feb. 6, 1922 97,928 Switzerland Feb. 16, 1923 

